Interestingly the 195 costs £5,685 less in Noise charges than the 319 the departure levies are similar and obviously passenger charges are similar per pax.
NOx is £8.82 per kg that will also be lower on the 195 so overall - Yes the 195 is cheaper.
We don't know what rates Flybe actually pay for leases do we or do you know different ?
Cost base of Flybe is certainly lower than BA and i suspect even their Mix fleet crews.